CVE-2015-7519: Phusionpassenger Phusion Passenger

Low severity, CVSS 3.7. EPSS: 2.4% chance of exploitation in the next 30 days.

agent/Core/Controller/SendRequest.cpp in Phusion Passenger before 4.0.60 and 5.0.x before 5.0.22, when used in Apache integration mode or in standalone mode without a filtering proxy, allows remote attackers to spoof headers passed to applications by using an _ (underscore) character instead of a - (dash) character in an HTTP header, as demonstrated by an X_User header.

Affected products

• Phusionpassenger Phusion Passenger: up to and including 4.0.59; version 5.0.0 only; version 5.0.1 only; version 5.0.2 only; version 5.0.3 only; version 5.0.4 only; …

Published 2016-01-08. Last modified 2026-06-17.